A drive device for performing a driving operation with the help of the property of a shape memory alloy is conventionally known (for example, see Patent Literature 1). Here, the property allows the alloy to contract when heated to a temperature equal to or greater than a certain temperature (operation temperature) by energization even if the alloy has been subjected to force and distorted.
This drive device includes: an insulating base member having an operation base part made up of one or more operation recesses on the upper surface; and a movable member which is opposed to the base member and has, on the opposing surface, operation projections to be inserted into the operation recesses. Between the opposing surfaces, a shape memory alloy material which is contracted by heat generated when energized is disposed while being curved to fit into the operation recesses of the base member.
Furthermore, the drive device includes biasing means for biasing the movable member toward the base member and is configured such that when de-energized, the movable member is pushed against the base member and the movable member is thereby overlapped with the base member. This is followed by the operation projections being brought into contact with the shape memory alloy material.
Then, when the shape memory alloy line is energized so as to be heated from that state to a temperature equal to or greater than a certain temperature, the super-elasticity causes the shape memory alloy line to be contracted and the movable member to be relatively moved when pushed by the shape memory alloy material so as to be separated away from the base member.
On the other hand, when the shape memory alloy line is de-energized and the temperature of the shape memory alloy line is lowered to a temperature equal to or less than a certain temperature, the movable member is returned to the original position when the movable member is pushed by the biasing means toward the base member. This is followed by each shape memory alloy line being returned to a curved shape (the shape when de-energized).